[PATCH] S3 suspend/resume with noexec v2

This patch is required for S3 suspend-resume on noexec capable systems.  On
these systems, we need to save and restore MSR_EFER during S3
suspend-resume.
Signed-off-by: "Venkatesh Pallipadi" <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/i386/kernel/acpi/wakeup.S

@@ -59,6 +59,14 @@ wakeup_code:
 	movl	$swapper_pg_dir-__PAGE_OFFSET, %eax
 	movl	%eax, %cr3
 
+	testl	$1, real_efer_save_restore - wakeup_code
+	jz	4f
+	# restore efer setting
+	movl	real_save_efer_edx - wakeup_code, %edx
+	movl	real_save_efer_eax - wakeup_code, %eax
+	mov     $0xc0000080, %ecx
+	wrmsr
+4:
 	# make sure %cr4 is set correctly (features, etc)
 	movl	real_save_cr4 - wakeup_code, %eax
 	movl	%eax, %cr4
@@ -89,6 +97,9 @@ real_save_cr4:	.long 0
 real_magic:	.long 0
 video_mode:	.long 0
 video_flags:	.long 0
+real_efer_save_restore:	.long 0
+real_save_efer_edx: 	.long 0
+real_save_efer_eax: 	.long 0
 
 bogus_real_magic:
 	movw	$0x0e00 + 'B', %fs:(0x12)
@@ -223,6 +234,20 @@ ENTRY(acpi_copy_wakeup_routine)
 	sldt	saved_ldt
 	str	saved_tss
 
+	movl	nx_enabled, %edx
+	movl	%edx, real_efer_save_restore - wakeup_start (%eax)
+	testl	$1, real_efer_save_restore - wakeup_start (%eax)
+	jz	2f
+	# save efer setting
+	pushl	%eax
+	movl	%eax, %ebx
+	mov     $0xc0000080, %ecx
+	rdmsr
+	movl	%edx, real_save_efer_edx - wakeup_start (%ebx)
+	movl	%eax, real_save_efer_eax - wakeup_start (%ebx)
+	popl	%eax
+2:
+
 	movl    %cr3, %edx
 	movl    %edx, real_save_cr3 - wakeup_start (%eax)
 	movl    %cr4, %edx

arch/i386/mm/init.c

@@ -438,8 +438,8 @@ static int __init noexec_setup(char *str)
 
 __setup("noexec=", noexec_setup);
 
-#ifdef CONFIG_X86_PAE
 int nx_enabled = 0;
+#ifdef CONFIG_X86_PAE
 
 static void __init set_nx(void)
 {

include/asm-i386/page.h

@@ -39,9 +39,9 @@
 /*
  * These are used to make use of C type-checking..
  */
+extern int nx_enabled;
 #ifdef CONFIG_X86_PAE
 extern unsigned long long __supported_pte_mask;
-extern int nx_enabled;
 typedef struct { unsigned long pte_low, pte_high; } pte_t;
 typedef struct { unsigned long long pmd; } pmd_t;
 typedef struct { unsigned long long pgd; } pgd_t;
@@ -49,7 +49,6 @@ typedef struct { unsigned long long pgprot; } pgprot_t;
 #define pte_val(x)	((x).pte_low | ((unsigned long long)(x).pte_high << 32))
 #define HPAGE_SHIFT	21
 #else
-#define nx_enabled 0
 typedef struct { unsigned long pte_low; } pte_t;
 typedef struct { unsigned long pmd; } pmd_t;
 typedef struct { unsigned long pgd; } pgd_t;